Point-of-care (POC) sample analysis systems are generally based on one or more re-usable test instruments (e.g., a reading apparatus) that perform sample tests using a single-use disposable testing device, e.g., a cartridge or strip that contains analytical elements, e.g., electrodes or optics for sensing analytes such as pH, oxygen and glucose. The disposable testing device can include fluidic elements (e.g., conduits for receiving and delivering the sample to sensing electrodes or optics), calibrant elements (e.g., aqueous fluids for standardizing the electrodes with a known concentration of analyte), and dyes with known extinction coefficients for standardizing optics. The instrument or reading apparatus contains electrical circuitry and other components for operating the electrodes or optics, making measurements, and performing computations. The instrument or reading apparatus also has the ability to display results and communicate those results to laboratory and hospital information systems (LIS and HIS, respectively), for example, via a computer workstation or other data management system. Communication between the instrument or reading apparatus and a workstation, and between the workstation and a LIS or HIS, can be via, for example, an infrared link, a wired connection, wireless communication, or any other form of data communication that is capable of transmitting and receiving electrical information, or any combination thereof. A notable point-of-care system (The i-STAT® System, Abbott Point of Care Inc., Princeton, N.J.) is disclosed in U.S. Pat. No. 5,096,669, which comprises a disposable device, operating in conjunction with a hand-held analyzer, for performing a variety of measurements on blood or other fluids.
One benefit of point-of-care sample testing systems is the elimination of the time-consuming need to send a sample to a central laboratory for testing. Point-of-care sample testing systems allow a nurse or doctor (user or operator), at the bedside of a patient, to obtain a reliable quantitative analytical result, comparable in quality to that which would be obtained in a laboratory. In operation, the nurse selects testing device with the required panel of tests, draws a biological sample from the patient, dispenses it into the testing device, optionally seals the testing device, and inserts the testing device into the instrument or reading apparatus. While the particular order in which the steps occur may vary between different point-of-care systems and providers, the intent of providing rapid sample test results close to the location of the patient remains. The instrument or reading apparatus then performs a test cycle, i.e., all the other analytical steps required to perform the tests. Such simplicity gives the doctor quicker insight into a patient's physiological status and, by reducing the time for diagnosis or monitoring, enables a quicker decision by the doctor on the appropriate treatment, thus enhancing the likelihood of a successful patient outcome.
In the emergency room and other acute-care locations within a hospital, the types of sample tests required for individual patients tend to vary. Thus, point-of-care systems generally offer a range of disposable testing devices with different sample tests, or combinations of tests. For example, for blood analysis devices, in addition to traditional blood tests, the different sample tests may include oxygen, carbon dioxide, pH, potassium, sodium, chloride, hematocrit, glucose, urea, creatinine and calcium, other tests can include, for example, prothrombin time (PT), activated clotting time (ACT), activated partial thromboplastin time (APTT), cardiac troponin I (cTnI), brain natriuretic peptide (BNP), creatine kinase MB (CKMB) and lactate. While devices typically contain between one and ten tests, it should be appreciated by persons of ordinary skill in the art that any number of tests may be contained on a device. For example, a device for genetic screening may include numerous tests. To illustrate the need for different devices, a patient suspected of arrhythmia may require a device with a test combination that includes a potassium test, whereas a patient suspected of a diabetic hypoglycemia may require a device with a test combination that includes a glucose test. An emergency room will need to have sufficient inventory of both types of testing device to meet the anticipated workload.
For hospitals, the introduction of point-of-care testing capabilities has created unique requirements and issues for quality compliance, system and operator verification, and process management. These issues arise from the use of one or more test instruments running multiple types of disposable sample testing devices at various locations within a hospital. Consequently, a hospital must provide an adequate supply of each type of device at each site of use, while ensuring the devices are within their usable shelf-life, along with also ensuring that the instruments are performing to specification. The Clinical Laboratory Improvement Amendments (CLIA) regulate laboratory testing and require clinical laboratories implementing point-of-care sample analysis systems to be certificated by their state as well as the Center for Medicare and Medicaid Services (CMS) before they can accept human samples for diagnostic testing. CLIA has established minimum standards for all non-waived laboratory testing, including specific regulations for quality control.
To achieve the goal of quality control, including the precision and accuracy of test results, it is necessary to be able to detect errors within the point-of-care systems as soon as possible. Conventionally, many point-of-care testing devices include unit-use cartridges and test strips (e.g., single-use disposable testing devices). With unit-use formats, analysis of liquid quality control can verify the performance of an individual test, but the analysis of liquid quality control consumes the test strip or cartridge and cannot guarantee the quality of tests from other strips or cartridges. Thus, unit-use tests often contain internal control processes built into each test to ensure result quality on each strip or cartridge. For example, U.S. Pat. No. 6,512,986 discloses a method of processing test results to detect any random and systemic exception from historical test results that have previously been stored. Further, U.S. Patent Application Publication No. 2002/0116224 discloses a networked expert system for automated evaluation and quality control of point-of-care laboratory measuring data.
However, with many point-of-care testing systems, issues arise in striking a balance between the use of liquid quality control and the reliance on internal control processes built into each test. For example, should an operator of a point-of-care testing device have to use liquid control for each reaction occurring on a sensing chip each day of testing, this could be cost prohibitive and duplicative of internal control processes built into the point-of-care testing system. With so many different point-of-care testing devices and control processes available, laboratories need a systematic approach to ensure quality and strike the right balance of liquid quality control in concert with internal control processes. This approach is known as risk management.
The Clinical and Laboratory Standards Institute (CLSI) guideline EP-23 introduces risk management principles to the clinical laboratory. CLIS EP23 describes good laboratory practice for developing a quality control plan based on the manufacturer's risk information, applicable regulatory and accreditation requirements, and the individual healthcare and laboratory setting. This guideline helps laboratories identify weaknesses in the testing process that could lead to error and explains how to develop a plan to detect and prevent those errors from happening. The CMS has incorporated key elements of risk management from CLSI EP23 into the new CLIA interpretive guidelines that offer a quality control option called an Individualized Quality Control Plan (IQCP). Specifically, laboratory tests, including point-of-care testing, now have two options for defining the frequency of quality control for non-waved testing (e.g., moderate- and high-complexity tests) including either two concentrations of liquid quality control each day, or developing an IQCP.
IQCPs are valuable to laboratories or medical care facilities that use single unit-use point-of-care devices and instrumentation with built-in control processes. The primary objective of IQCPs is not to reduce the frequency of analyzing liquid quality control, but rather to ensure the right quality control to address a laboratory's or medical care facility's specific risks and ensure quality test results. In the context of point-of care testing, laboratories or medical care facilities may incorporate both internal and external control processes. Each device is unique, operates differently, and offers specific control processes engineered into the test. And since no single control process can cover all potential risks, a laboratory's or medical care facility's quality control plan should incorporate a mix of internal controls and traditional liquid quality control.
Each test may require a specific IQCP, because devices are different and present unique risks. However, a single risk assessment and IQCP could cover multiple tests conducted on the same instrument, provided the IQCP factors in the differences unique to each analyte. For instance, a single IQCP for a chemistry analyzer could cover all tests conducted on that analyzer, since instrument operation, risk of error, and functionality of control processes is shared amongst all analytes on the same analyzer. IQCPs should benefit medical care facilities in a number of ways. For example, laboratories or medical care facilities using single unit-use devices may define an optimum frequency of liquid quality control in conjunction with a manufacturer's control processes. For unit-use blood gas and coagulation devices, medical care facilities can be more efficient by analyzing quality control for lots of reagents using a subset of devices rather than every device available, since the chemistry of the test is in the unit-use strip or cartridge—not in the device, which acts as a volt-meter or timer. For molecular arrays and labs-on-a-chip, analyzing liquid quality control across each reaction may be less effective than controlling the processes of greatest risk, such as quality and amount of sample, viability of replicating enzyme, and temperature cycling.
Quality control programs, especially point-of-care quality control programs, which monitor numerous instruments and types of devices interconnected within a network, tend to yield large volumes of quality control information obtained from numerous point-of-care locations within the network. Accordingly, several computer implemented methods have been proposed to process the large volumes of quality control information. These computer implemented methods often include processes for determining potential quality control compliance issues. However, the performance of risk management to ensure quality and strike the right balance of liquid quality control in concert with internal control processes has not been adequately addressed. Nor has there been a quality control program implemented using a centrally managed system that ensures only biological sample testing devices that pass a quality assurance protocol are used for point-of-care testing.
For example, U.S. Pat. Nos. 6,856,928 and 6,512,986 disclose a method for analyzing data from point-of-care testing to identify when the testing exceeds a variation expected under stable operation (i.e., the testing is “out of control”). The method includes storing test results received from each of a plurality of point-of-care devices, including an association with the operator of the point-of-care device and/or a reagent used in obtaining the test results. The method further includes processing the results to detect any random and/or systemic exception from results that have previously been stored, and automatically disabling a questionable point-of-care device based on detection of a quality control compliance exception This method, however, is predicated on quality control rules, such as Westgard Rules, for automatically disabling a particular point-of-care device based on detection of an exception, and does not strike a balance of the liquid quality control in concert with internal control processes nor ensure only biological sample testing devices that pass a quality assurance protocol are used for point-of-care testing.
U.S. Pat. No. 8,495,707 discloses system for quality assured analytical testing. The system includes an Instrument Management System and an analytical instrument for conducting analytical testing, the analytical instrument having an input section for determining an actual user of the instrument and the analytical instrument being configured to run a testing routine. The system further includes a terminal connected to the Instrument Management System, which is remote from the analytical instrument and which provides an examination module of the Instrument Management System that is programmed to conduct an exam during which the examination module prompts questions to the user via the terminal which relate to the analytical instrument and/or a diagnostic test to be conducted therewith, receive and evaluate answers to the exam, and transmit a user certificate to the analytical instrument if the user passed the exam such that a user may access a testing routine. This method, however, is predicated on control of instrument usage so that only well-educated users with proven knowledge are allowed to perform testing with the analytical instrument, and does not strike a balance of liquid quality control in concert with the knowledge testing nor ensure only biological sample testing devices that pass a quality assurance protocol are used for point-of-care testing.
U.S. Patent Application Publication No. 2004/0173456 discloses a system for point-of-care diagnosis including a cartridge for analysis, where cartridge-specific data are evaluated for the respective concentration values in accordance to the cartridge specific data and information. Additionally, U.S. Pat. No. 7,824,612 discloses a body fluid analyzer with a data storage unit that contains information concerning a particular drug being taken by a patient, and a processor for setting a threshold value for an analyte to be sensed by a sensing unit and a display for displaying an alert. As with other disclosed methods of point-of-care quality control programs, these methods do not strike a balance of liquid quality control in concert with internal control processes nor ensure only biological sample testing devices that pass a quality assurance protocol are used for point-of-care testing.
In view of the above-noted limitations of conventional point-of-care testing systems and the recent implementation of IQCPs by many laboratories and medical care facilities, there remains a need for systems and methods of determining quality compliance for a set of biological sample testing devices, e.g., single-use blood testing cartridges, used with one or more test instruments at the point-of-care in a hospital or other location for delivering medical care, where the systems and methods implement risk management to ensure that only devices that pass a quality assurance are used for point-of-care testing.